Preheat the oven to 375°F (190°C) and line a baking sheet with parchment paper or lightly grease it with oil.

Place the quark in a mixing bowl. If it is very wet, let it drain briefly in a sieve, then add it to the bowl.

Add the egg, sugar, vanilla, oil or melted butter, salt, and any optional cinnamon or lemon zest. Stir with a spoon until smooth.

Add the oats and baking powder, and stir until everything is evenly combined. If using raisins or other mix-ins, fold them in now.

Let the mixture rest for 5 minutes so the oats can swell slightly and the batter thickens and holds its shape.

Using a spoon or damp hands, portion the batter into about 12 small mounds on the prepared baking sheet, spacing them slightly apart.

Gently flatten each mound into a round, about 1/2 inch (1–1.5 cm) thick, to form small taler.

Bake in the preheated oven for 15–18 minutes, until the taler are lightly golden at the edges and set in the center.

Remove from the oven and let cool on the tray for a few minutes, then transfer to a rack. Serve warm or at room temperature, plain or with yogurt, fruit, or a little nut butter.